Peritoneal dialysis apparatus

ABSTRACT

A peritoneal dialysis apparatus comprising a plurality of components including a catheter, a fluid heater, a fluid weighing means and a control device. The components are interconnected by conduits so that fluid can flow from the heater to the peritoneal cavity by way of the catheter, and then from the peritoneal cavity to the weighing means. The weighing means measures the quantity of discharged fluid as a result of the introduction of the dialysis fluid to check that the dialysis fluid is causing fluid to drain from the peritoneal cavity. The flow of fluid between the components of the system is controlled by valves which are selectively opened and closed.

States tent 1 1 1111 3,872,863

Lasher et al. Mar. 25, 1975 [54] PERITONEAL DIALYSIS APPARATUS 3,783,8661/1974 Tirkkonen 128/213 [75] Inventors: Norman Lasker, Gladwyn; BruceE. FOREIGN PATENTS OR APPLICATIONS Jarrell, i p i both of 1,964,7337/1971 Germany 128/213 P [73] Asslgnee $3 3??? 2 fdlcal mducts CorpPrimary Exammer-Dalton L. Truluck Attorney, Agent, or FirmSeidel, Gonda& [22] Filed: July 31, 1973 Goldhammer 21 A l. N 384,316 1 pp 57ABSTRACT A peritoneal dialysis apparatus comprising a plurality [52]U.S.3l. 125862313; 128/2314 E of components including a catheter, afluid heater, 3 [51] 'f g' fluid weighing means and a control device.The com- [58] held 0 earc & 1 1 ponents are interconnected by conduitsso that fluid 1 can flow from the heater to the peritoneal cavity by wayof the catheter, and then from the peritoneal cav- [56] References Cltedity to the weighing means. The weighing means meas- UNITED STATESPATENTS ures the quantity of discharged fluid as a result of the2,625,932 1/1953 Salisbury 128/2142 introduction of the dialysis fluidto check that the dial- 2,707,955 5/1955 Borden 128/278 ysis fluid iscausing fluid to drain from the peritoneal 3,410,268 l 6 Lelwci cavity.The flow of fluid between the components of the system is controlled byvalves which are selectively ys e a. 3,709,222 1/1973 De Vries 128/213Opened and Closed 3,730,183 5/1973 Goldsmith et a1. 128/213 10 Claims, 9Drawing Figures flsrarr i- IVE/6H7?" HE/Gfll'i? w 46 HE/6Hf4- 9; I24

i /75 w 66 1 Him/r5 k PERITONEAL DIALYSIS APPARATUS This inventionrelates to a dialysis apparatus and more particularly to a peritonealdialysis apparatus.

Peritoneal dialysis is a well known medical procedure for removingimpurities from the blood stream. It is accomplished by introducing asuitable dialysis fluid into the peritoneal cavity and then withdrawingthe fluid after a suitable period of time. During the time that thedialysis fluid is in the peritoneal cavity, impurities in the bloodstream are drawn through the walls of the blood vessels on the abdominalwall and in the viscera, and through the peritoneum membrane againstwhich they lie through the osmotic effect of the dialysis fluid. Theentire procedure may take up to 36 hours since the dialysis fluid mustbe replaced from time to time as the concentration of impurities in itincrease.

Heretofore, peritoneal dialysis has been done in hospitals because ofthe high risk of infection and because trained personnel need to beavailable to perform the procedure.

Accordingly, the invention relates to a peritoneal dialysis apparatuswhich can be .used by a patient at home thereby enabling the hospitalbed to be free for use by others, and thus reducing the cost of thedialysis to the patient.

To this extent, the apparatus comprises means for supplying dialysisfluid to a means for measuring prede termined quantities and means forconducting the dialysis fluid to a catheter. The catheter is connectedto the peritoneal cavity of a patient and to a means for detecting aminimum quantity of dialysis fluid. Means are provided for regulatingthe flow of dialysis fluid through the apparatus.

The invention can best be described by referring to the attacheddrawings wherein a presently preferred form of the invention isillustrated and wherein FIG. 1 is a schematic drawing of a preferredform of the apparatus.

FIG. 2 is a sectional view of the means for controlling the flow offluid through the apparatus.

FIG. 3 is a sectional view taken along line 33 of FIG. 2.

FIG. 4 is a sectional view taken along line 4-4 of FIG. 2.

FIG. 5 is a perspective view of a portion of the apparatus illustratedin FIG. 1 for weighing fluid discharged from the peritoneal cavity.

FIG. 6 is a perspective view of a portion of the apparatus shown in FIG.1 which is used for heating the dial ysis liquid.

FIG. 7 is an end view taken along line 7-7 of FIG. 6.

FIG. 8 is a schematic view of the circuitry for operating the apparatus.

FIG. 9 is a drawing graphically portraying the operation oftheapparatus.

Now referring to the drawing for a detailed description of theinvention, a peritoneal dialysis apparatus is schematically illustratedby the numeral 10 in FIG. 1.

The apparatus 10 comprises a container 14 in which a supply of dialysisfluid is stored for use as needed, a means 16 for metering and heatingthe dialysis fluid after it is. dispensed from container 14, a catheter(schematically) 18, a means for detecting discharge of fluid from thepatient 20, a means for receiving fluid discharged from the apparatus 22and a means for con- 2 trolling the flow of dialysis fluid through theapparatus 24.

A pump or other positive driving means may be used to move the fluidthrough the apparatus. However, its construction is greatly simplifiedand its reliability is substantially increased by relying on the forceof grav- 1ty. Accordingly, the components of the apparatus are supportedby a suitable means indicated schematically by numeral 21 atsuccessively lower heights than the preceding components. The successivecomponents in the apparatus may be interconnected by suitable resilientflexible plastic conduits. A typical plastic is commercially availableand is sold as tubing under the trademark TYGON."

The container 14 may be of any convenient size. Preferably it shouldcontain enough dialysis fluid to enable a complete dialysis procedure tobe performed and should be constructed so that the dialysis fluid can bekept sterile. An outlet 25 in the bottom of the container connects itwith the rest of the system. Fluid used in peritoneal dialysis arecommercially available and are well known to those skilled in the art. Atypical fluid is sold under the trademark DIANEAL by TravenolLaboratories.

The means for metering and heating the dialysis fluid 16 is best seen inFIGS. 6 and 7.. It includes an outer housing 26 which may be of anyconvenient shape. A heating unit is supported in housing 26 by aplurality of fasteners 28. It comprises front and rear thermallyconductive plates 30 and 32 which are arranged in spaced parallelrelation to each other. Each of plates 30 and 32 supports a heatingelement 34 and 36. The heating elements cover a substantial area ofplates 30 and 32 to rapidly bring the plates to the desired temperature.A collapsible sterile bag 35 which may be made from TYGON is supportedwithin housing 26. A typical means for supporting the bag may includesuspending it from a rod 36 which is slipped through a sleeve along oneedge of the bag. The bag 35 :may have any convenient volume. However itis preferred that the volume be about two liters since introduction anddischarge of this volume of fluid into the peritoneal cavity atintervals during the procedure achieves satisfactory results. A bag ofreduced volume may be selected when the patient is a child.

The plates 30 and 32 are connected in a circuit which enables them tobring the dialysis fluid in bag 35 to a temperature of about 30 C. Thecircuit which will be described herein includes a thermal switch 38 incontact with the bag 35. An outlet 39 in the bottom of the bag connectsit to the rest of the apparatus. Since the bag 35 is collapsible it canbe filled and emptied without exposing its contents to the air.

The catheter 18 may be permanently implanted in the patient or it may bea disposable catheter. Both types of catheters are well known and arecommercially available for use in peritoneal dialysis.

The means for detecting discharge of fluid from the patient 20 can best.be seen in FIG. 5. It may be mounted to a support frame (not shown) by abracket 44. The bracket supports a pin 46 which serves as a fulcrum foran elongated lever arm 48. A collapsible bag 50 for collecting fluiddischarged from the patient is supported at one end of lever arm 48. Theother end of lever arm 48 is connected to a counterweight such as spring52. A second bracket 53 on the support frame carries a microswitch 54 sothat the operator of the microswitch is in contact with the lowersurface of lever arm 48.

The volume of bag 50 may be about three liters so that if any fluid hascollected in the peritoneal cavity, it also will be discharged alongwith the dialysis fluid. The counterweight is selected-so thatmicroswitch 54 is closed 'until a sufficient volume of fluid, preferablyabout 1500 grams, is collected in bag 50. At 1500 grams, the force ofthe counterweight is overcome and the lever arm 48 rotates about pin 46to open microswitch 54. The microswitch is connected to an alarm signalin a manner which will be explained herein.

Normally, microswitch 54 is closed. However, if at a predeterminedinterval microswitch 54 is still closed, the alarm is activated tonotify the patient that the expected quantity of fluid has not drainedfrom the peritoneal cavity.

The means for receivingfluid discharged from the apparatus 22 maycomprise any convenient receptacle such as a disposable bag. In thealternative it could be a conventional drain.

The container 14 is connected to both the means for heating and meteringdialysis fluid 16 and the inlet of catheter 18. To this extent a lengthof tubing 60 is connected between the bottom opening 25 in container 14and an arm of a T 62. Another length of tubing 64 is connected betweenthe second arm of the T 62 and the opening 38 in the means for heatingand metering dialysis fluid 16. The third arm of T 62 is connected by alength of tubing 66 to the catheter 18.

The outlet of the catheter 18 is connected to both the means fordetecting discharge of fluid from the patient 20 and the means forreceiving discharged fluid 22. To this extent a length of tubing 70 isconnected between the catheter l8 and one arm of a T 72. Another lengthof tubing 74 is connected between a second arm of T" 72 and the bag 50.The third arm of T 72 is connected to the means for receiving dischargedfluid 22 by a length of tubing 76.

The lengths of tubing 60, 66, 70 and 76 pass through control means 24.

From FIG. 1 it is apparent that the control means 24 may comprise firstand second valves 80 and 82. First valve 80 selectively opens and closestubes 60 and 70. Second valve 82 selectively opens and closes tubes 66and 76. The valves regulate the flow of fluid through the apparatus.

When valve 80 is open and valve 82 is closed, the fluid in container 14is permitted to flow through tubes 60 and 64 into the heating andmetering means 16. Simultaneously, fluid is drained from the patientthrough the catheter 18 and tubes 70 and 74 into bag 50.

When the valve 82 is open and valve 80 is closed, fluid flows from theheating and metering means through tubes 64 and 66 into catheter 18 andthence into the patient. Simultaneously fluid is drained from the bag 50through conduits 74 and 76 into the discharge receiving means 22.

Thus, by controlling the duration of time for which the valves 80 and 82are opened and closed and by regulating the volume of dialysis fluidwhich can be stored in the heating and metering means 16, an efficient,safe peritoneal dialysis apparatus is achieved. Significantly, it shouldbe noted that bag 50 is provided on the downstream side of the patientin order to detect an insufflcient drainage of fluid from theperitonealcavity.

The control means 24 is illustrated in FIGS. 2-4. It comprises a housing86 which rotatably supports a shaft 88 in bearings 89. The shaft 88 isconnected by way of a clutch 90 to the output shaft 92 of a motor 94.Output shaft 92 is rotatably supported by bearing 95.

Shaft 88 supports cams and 102 which operate valves 80 and 82respectively, and earn 104 which operates microswitches 108 and 110.Cams 100 and 102 have profiles that correspond to FIG. 9 wherein it isseenthat each valve 80, 82 opens slowly and closes quickly. Themicroswitches 108 and 110 are supported by housing 86 so that theiroperators can be displaced into a notch formed in the cam (see FIG. 8).Hence rotation of cam 104 through a complete revolution causes eachmicroswitch to be tripped once. The cams 100 and 102 are supported onshaft 88 so that they are 180 out of phase with respect to each other.Thus when one of valves 80 and 82 is open, the other is closed. As willbe explained in greater detail herein, the power to motor 94 is suppliedthrough microswitches 108 and 110. When the switch operators fall intothe notch in the cam, the motor 94 is stopped. This positions the valves80 and 82 in accordance with the configuration of cams 100 and 102 untilthe motor is energized through the microswitch whose operator is not inthe notch.

Each valve includes a stem 114 with a cross bar 118 at oneend and, ifdesired, a roller 120 at its other end. Each valve stem 114 includes aradially directed flange 122 near roller 120.

The valve stems 114 are supported in apertures 123 formedin a supportmember 124 mounted in housing 86. Each of valve stems is biased towardits respective cam 100, 102 by a spring 126 which bears against theflange 122.

A plate 130 is supported in spaced relation from the front wall ofhousing 86 by a suitable hinge 132. Suitable latching means such asmember 134 may be provided for retaining plate 130 in the positionillustrated in FIG. 2.

Plate 130 supports a housing 138 having the appearance of a frame with acentral opening 139. The housing 138 is comprised of two separatemembers 140, 142 which have grooves in which the tubes can be received.When the members 140, 142 are assembled the tubes are held in theposition illustrated in FIGS. 2 and 4. Thus, tubes 60 and 70 arepositioned so that they can be pinched closed by valve 80. Tubes 66 and76 are positioned so that they can be pinched closed by valve 82.

A layer of relatively soft backing material 148 such as foam rubber,felt or the like is secured to plate 130 adjacent tubes 60, 70, 66 and76.

Suitable means is provided for selectively energizing motor 94 atpredetermined intervals during the dialysis treatment. The motor causesshaft 88 to rotate with the result that the tubes 60 and 70, and 66 and76 are alternately pinched and released to permit fluid to flow throughthe apparatus.

The energization means for the motor comprises the circuit illustratedschematically in FIG. 8.

The circuit comprises timers 150A, 1503 and 150C, a two-positionlatching relay 156, an alarm signal 158 and a counter 160.

Additionally, the circuit includes the heating plates 34 and 36, thermalswitch 38, switch 54, motor 94 and switches 108 and 110.

The circuit is energized by closing on-off switch 162. Switch 164, whichmay be called the fill switch, is operative when closed to cause thedialysis fluid in bag 35 to enter the patient by way of catheter 18.Switch 166, which may be called the drain switch, is operative whenclosed to cause the dialysis fluid in the patient to be dischargedtherefrom into bag 50.

On-off switch 162 may be a two-position push button switch. When theswitch is OFF a circuit is completed across terminals 170 and 172. Whenthe switch is ON a circuit is completed across terminals 174 and 176.Fill switch 164 may be a push button switch which is biased to anormally OPEN position. However, when the push button is monentarilyCLOSED," a circuit is enabled across terminals 180 and 182.

Drain switch 166 may be a push button switch of the same type as switch164 in that it is biased to a normally OPEN" position. In its OPENposition it enables a circuit across terminals 186 and 188. When thisswitch is momentarily CLOSED a circuit is enabled across terminals 190and 192.

Timers which may be used satisfactorily in the invention are identifiedcommercially as Singer Industrial Timers, Type GTD, 30 minutes. Thesetimers may be set to run for a maximum time of 30 minutes. Each timer150A, 1508 and 150C is essentially the same. Thus, the same part in eachtimer is identified by the same reference numeral with the differenttimers being distinguished by the letters A, B and C following thenumerals.

The following description will suffice for all timers 150. Each timerincludes a switch 196 which is comprised of contacts 198 and 200 andthrow 202. It also includes a timer motor which is'connected by anelectrically energized clutch to throw 202.

The timer motor runs continuously as long as power is applied to motorterminal 204.

The clutch is energized as long as power is applied to clutch terminal206. Every time the clutch is energized, the timer is reset to themaximum time thereon (this feature is an aspect of the particular timeridentified herein).

Both the timer motor and the clutch are connected to common terminal208. While the motors are connected to the throws by the clutches, thethrows 202 engage contacts 198 in each switch 196. When each timer hasrun out, the throws 202 move from contacts 198 to contacts 200.

Relay 156 includes three separate but interconnected single throwswitches. In each switch the throw, 210 212 and 214, respectively ismovable between first and second contacts 210A and 2108, 212A and 2128and 214A and 214B.

The throws are shifted by energizing coil 11" or L2. Energization ofcoil L1 completes a circuit through contacts 210A, 212A and 214A.Energization of coil L2 completes a circuit through contacts 210B, 2128and 2148. The throws remain in engagement with the contacts until theother coil (L1 or L2) is energized, then they shift.

The source of electromotive force 221, which may be an ordinaryelectrical outlet, is connected by way of fuse 223 to terminals 170 and174 on on-off switch 162.

The circuit is designed so that when the apparatus is shut off the relaythrows are at rest on contacts 210A, 212A and 214A. Therefore theapparatus always starts on that portion of its cycle which permits fluidto be drained from the patient into bag 50. The mechanism by which thisoccurs is explained herein.

Upon the closing of on-off switch 162 on terminals 174 and 176 a numberof circuits are completed or enabled from the source of power 221 andfuse 223. These circuits permit fluid to be discharged from the patientfor a predetermined interval as will be explained herein.

Thus, a circuit is completed to motor 94 from on-off switch terminal 176by Way of lines 220, 222 and through switch 108. A circuit is completedto thermal switch 38 and heater plates 34, 36 by way of lines 220, 224,226, 228 and 230.

The motors and clutches on timers 1508 and 150C are energized and thetimers begin. to wind down by virtue of circuit through drain switch 166and relay 156. The circuit includes lines 224, terminals 190, 186 and188, line 232, relay contact 214A and line 234.

The motor and clutch of timer 150C is energized by way of line 234 andlines 236 and 238 which are connected to timer motor terminal 204C andclutch terminal 206C.

Switch 106C receives power by way of lines 234, 240 and throw 202C.Since throw 202C is touching contact 198C, a circuit is completed'by wayof line 242 to the motor terminal 204B in timer 150B. An indicator lampmay be connected to line 242 toindicate when the timer motor isenergized. Clutch terminal 2068 receives power from line 236 by way ofline 244.

The motor 94 causes shaft 88 to rotate in the direction indicated by thearrow in FIG. 8 until the operator of switch 108 falls into the notch incam 104. This opens the circuit to the motor thereby halting therotation shaft 88. By virtue of the positions of cams and 102 on shaft88 they have been rotated to the position illustrated in FIG. 2 wherevalve 80 is open and valve 82 is closed. As illustrated in FIG. 1, whenthe valves are in this configuration dialysis fluid is permitted todrain from container 14 to the heating and metering means 16 and at thesame time fluid is permitted to drain from the patient by way ofcathether 18 into the bag 50.

If for some reason, cam 104 is not in the position illustrated whenon-off switch 162 is closed and switch 108 is open, the motor 94 will:not operate since the valves 80 and 82 will be in the correct positionsto permit fluid to be drained from the patient.

Timer C is set to run for a shorter time than timer 150B. Timer 150Ccooperates with switch 54 to indicate that fluid is draining from thepatient at an adequate rate. To this extent a circuit is normallyenabled through switch 54 by way of contact 200C in timer 150C, line254, switch contact 256 and line 258 to alarm 158. But when the weightof fluid in bag 50 reaches 1500 grams, or any predetermined weightdeemed desirable, the throw in switch 54 is moved to contact 260.

With the foregoing in mind, when timer 150C runs out, as for examplefifteen minutes after it is energized, throw 202C moves to contact 200C.If the predetermined quantity of fluid is 'not :in bag 50, the circuitthrough alarm 158 is completed by way of line 254, contact 256 and line258. The alarm 158 may be visible, audible or a combination of both,provided it alerts the patient to the fact that inadequate drainage fromthe body is taking place. Since there is no power in line 242, the motorin timer 150B is stopped. Thus, the apparatus remains in the drainportion of the cycle and the alarm 158 remains energized until theapparatus is shut off or the fill switch 164 is depressed.

If an adequate amount of fluid is in bag 50 when timer 150C runs out,the alarm is bypassed and power to motor terminal 2048 is achieved byway of line 254,

contact 260 and line 242.

Assuming that there has been adequate drainage to bag 50, when the timeon timer 150B runs out, throw 202B moves to contact 200B to startfilling the patient with dialysis fluid. This energizes coil L-2 inrelay 156 by way of lines 226, 264, throw 202B, contact 2008, lines 266and 268. Coil L2 moves all of the throws in the relay clockwise so thatcircuits are completed to terminals 2103, 2128 and 214B.

Energization of coil L2 energizes counter 160 by way of lines 266, 270and 272. Hence a count is taken on each time the circuit shifts to causedialysis fluid to enter the patient.

Clockwise movement of the relay throws 210, 212 and 214 completes orenables a number of circuits.

A circuit is completed to motor 94 through line 222, relay contact 212Band'through switch 110. The switch is closed since the notch in cam 104is now adjacent switch 108. The motor rotates shaft 88 until theoperator on switch 110 falls into the notch whereupon the motor stopsrotating the shaft. At this point valves 80 and 82 are in the positionsillustrated in FIG. 1 wherein fluid is permitted to fill the patient byway of cathether 18 from the heating and metering means 16 and the fluidin bag 50 is permitted to be discharged to the drain means 22.

The motor and clutch on timer 150A are energized and the timer begins towind down by way of a circuit through relay throw 214, relay contact2148. and line 276. Line 276 is connected to motor terminal 204A andclutch terminal 206A. An indicator lamp may be coupled to motor terminal204 to indicate that the motor is energized.

The throw 202A in switch 196A is on contact 198A while the timer isrunning. When the time on timer 150A runs out, after, for example 30minutes, throw 202A shifts to contact 200A to complete a circuit throughcoil .L{ by way of line 280, relay throw 202A and lines 282, 284 and286.

Energization of coil L shifts all the relay throws in relay 156counterclockwise so that they engage contacts 210A, 212A and 214A. Thiscompletes a circuit through timer 150B and timer 150C so that the cycleis repeated as described above. In the event that timer 150C should runout before an adequate amount of fluid is received in bag 50, alarm 158will be energized.

When timer 150B runs out the relay 156 shifts and the motor 94 energizedto rotate shaft 88 to permit dialysis fluid to again fill the patient.At the same time, timer 150A is energized.

Significantly, it should be noted that the timers are reset to themaximum time thereon each time they are energized. In timers 150A and150B the maximum time is externally adjustable. To this extent, they maybe mounted on a panel and have knobs extending therefrom for thatpurpose.

On the other hand, timer 150C is designed to be nonadjustable. Thus, itmay be set at the factory. It is preferably permanently mounted withinan enclosing structure so that it cannot be tampered with by the user.

At any time in its cycle the apparatus may be shut down by moving switch162 to the OFF position so that it completes a circuit across terminalsand 172.

If the relay throws are in their clockwise positions when on-off switch162 is moved to its OFF position, a circuit is completed to coil L1 fromterminals 170 and 172 by way of line 290, relay contact 2108, and lines292, 284 and 286. This moves the throws counterclockwise which thenopens the circuit from on-off switch 162 since relay contact 210A is notconnected to the rest of the circuit.

If, on the other hand, the relay is closed on contact 210A, movingswitch 162 to its OFF position so that it completes a circuit acrossterminals 170 and 172 merely shuts down the apparatus.

The apparatus can be switched from the drain cycle to the fill cycle orfrom the fill cycle to the drain cycle by depressing fill switch 164 ordrain switch 166 respectively.

For example, if the apparatus is draining fluid from the patient and itis desired to switch it to fill the patient, switch 164 is depressedmomentarily to complete a circuit across terminals and 182. Thiscompletes a circuit from the source of electromotive force throughcontacts 174 and 176, line 220, through switch 164 by way of terminals180 and 182, and line 294. Counter 160 is energized by way of lines 294and 272. Coil L2 is energized by way of lines 294, 270, and 268. Whencoil L2 is energized, it shifts the throws (they are in theircounterclockwise position when fluid is draining from the patient). Thiscompletes a circuit to relay contact 2128 and a circuit to relay contact2143 so that circuits are completed through switch 110 to motor 94 andto timer motor and clutch terminals 206A and 204A in timer 150A. Shaft86 rotates until switch 110 opens thereby deenergizing motor 94. Thisopens valve 82 to fill the patient from the metering and heating means22.

When the time on timer 150A runs out, throw 202A moves to contact 200A.This completes a circuit from terminal 176 in on-off switch 162 to coilL1 by way of line 280, throw 202A, contact 200A and lines 282, 284 and286. Energization of coil L1 shifts the relay throws counterclockwise toenergize and reset timers 150B and 150C and motor 94 (through switch108) to start the drain portion of the cycle.

The drain cycle continues as explained above with both timers 150C and150B being energized. If timer 150C runs out before an adequate amountof fluid is in bag 50 an alarm is sounded.

On the other hand, if an adequate amount of fluid is in bag 50 whentimer 150B runs out, the relays are again thrown and the fill portion ofthe cycle takes over.

If the apparatus is in the fill portion of its cycle and it is desiredto shift it to the drain portion, switch 166 is depressed momentarily tocomplete a circuit across terminals and 192. This completes a circuit tocoil L1 by way of terminal 192 and lines 296 and 286. Energization ofcoil L1" shifts the relay throws counterclockwise to complete circuitsto relay contacts 212A and 214A so that circuits are completed to motor94 and to timers 1508 and 150C. In this regard, the circuit componentsassume the same configuration that they have when on-off switch 162 ismoved to its ON" position as described in detail above.

From the foregoing it is apparent that at any part of its cycle theapparatus can be shifted to the opposite part of the cycle.

In order to use the apparatus described, each of the components of thesystem, namely, container 14, metering and heating means 16, the patientand catheter 18, the weighing means 20 and the drain 22 are arranged sothat each component has a higher elevation than the component followingit so that the natural tendency of the dialysis fluid in container 14 isto flow through the apparatus.

The sequence of operation of the apparatus is shown in FIG. 9. Theapparatus can go through a complete cycle in up to one hour. Up to 30minutes can be used to fill the patient. and up to 30 minutes can beused to drain the patient. The duration of the fill and drain intervalsare controlled by timers 150A. and 1508. Since the timers are externallyadjustable these periods can be varied as desired.

The motor 94 is energized at the end of each fill and each draininterval. The motor is selected so that each time it is energized shaft88 rotates through half a turn in about 30 seconds. As explained earlierthe motor is energized at the end of each fill and drain interval. Cams100 and 102 are profiled to enable valves 80 and 82 to graduallyopenover each thirty second interval of shaft rotation, but to closeabruptly. This is so that the dialysis fluid does not surge or dripthrough the tubing. During each thirty second period of cam rotation,the positions of valves 80 and 82 are reversed, and, due to cam 104, oneof microswitches 108, B is opened while the other is closed.

A commercial embodiment of the invention would comprise sufficientdialysis fluid in container 14 to discharge a two liter does of dialysisfluid into the patient every half hour with the succeeding half hourbeing consumed in withdrawing the dialysis fluid. Thus, the heater bagacts as a measuring device in order to control the amount of fluid beingintroduced to the peritoneal cavityin any given time.

It is contemplated that with the present apparatus a complete dialysiscan be achieved in a period of about 10 hours as opposed to an intervalof 36 to 72 hours as in present procedures.

The substantial reduction in time is achieved by virtue of the fact thatthe dialysis fluid is changed rather rapidly.

Thus, it is a well known fact that in an osmotic process, as the fluidson each side of the membrane approach equilibrium, the rate of exchangeacross the membrane decreases. Thus, it is advantageous to change thedialysis fluid as the rate of transfer across the peritoneal membranebegins to slacken.

This can readily be done with the present apparatus by merely externallyadjusting the time available on timers 150A and 1508.

At the same time since the presence of an attendant is not necessary inorder to change the fluid in container 14, a sufficient amount of fluidin order to perform the entire dialysis may be made available at onetime. lt is contemplated that an adequate amount of fluid tosatisfactorily dialyze an adult patient would be about liters. Thus,over a period of 10 hours, at a rate of 2 liters per cycle, the entirequantity of fluid would be consumed.

Significantly, at the end of each cycle of the apparatus, the fluiddischarged from the peritoneal cavity is weighed in order to assure thatthe patient is draining properly. In the event that inadequate drainageis taking place, a suitable alarm is activated.

A further safety device is present by virtue of the fact that when theapparatus is initially turned on as, by pushing switch 162 to close acircuit across terminals 174 and 176 the apparatus automatically startson a drain cycle. Thus, there is no possibility that two liters ofdialysis fluid would be in the patient as two additional liters arebeing introduced.

Finally, it should be noted that the apparatus always shuts off in thedrain position.

While the invention has been described with respect to one preferredembodiment thereof, it is apparent that many other forms and embodimentswill be obvious to those skilled in the art in view of the foregoingdescription. Thus, the scope of the invention described herein shouldnot be limited by that description but, rather, only by the scope of theclaims appended hereto.

We claim:

1. A dialysis apparatus comprising first means for supplying dialysisfluid, second means for measuring a predetermined quantity of dialysisfluid, a catheter, third means for detecting a minimum quantity ofdialysis fluid, means for supporting said first means above said secondmeans, said second means above said catheter, and said third means belowsaid catheter so that dialysis fluid moves through said apparatus underthe force of gravity, fluid flow conduits interconnected between saidfirst and second means, said second means and said catheter and saidcatheter in said third means, fourth means for regulating the flow ofdialysis fluid and said conduits between said first and second means andsaid catheter and said third means, fifth means for regulating the flowof dialysis fluid between said second means and said catheter, and fromsaid third means, and means for controlling said fourth and fifth meansto alternately permit flow of dialysis fluid in the conduits regulatedthereby so that the dialysis fluid is permitted to flow through saidapparatus and a patient and then from said third means.

2. A dialysis apparatus as defined in claim 1 including an alarm, meanscoupling said third means to said alarm, and means for enabling saidalarm if said third means fails to detect a minimum quantity of dialysisfluid.

3. A dialysis apparatus as defined in claim 2 wherein said third meanscomprises a frame, an arm, said arm being pivotally supported by saidframe intermediate its ends, a fluid receptacle coupled to said arm onone side of said pivot, means comprising a counterweight coupled to saidarm on the other side of said pivot, and said means for enabling saidalarm is disposed adjacent said arm for actuation thereby if the weightof dialysis fluid in said fluid receptacle is insufficient to overcomethe force of said counterweight means.

4. A dialysis apparatus as defined in claim 1 wherein said second meansincludes means for heating dialysis liquid therein to a predeterminedtemperature.

5. A dialysis apparatus as defined in claim 1 including a fluid flowconduit extending from said third means, and a discharge receptacleconnected to said last named fluid flow conduit to receive dialysisfluid from said third means.

6. A dialysis apparatus as defined in claim 1 wherein said control meanscomprises a shaft, first and second cams mounted on said shaft, one ofsaid cams controlling said fourth means, the other cam controlling saidfifth means, energizable means for rotating said shaft, and means forselectively energizing and de-energizing said energizable means toselectively rotate said shaft.

7. A dialysis apparatus comprising first means for supplying dialysisfluid, second means for measuring a predetermined quantity of dialysisfluid, a catheter, third means for detecting a minimum quantity ofdialysis fluid, said third means comprises a frame, an arm, said armbeing pivotedly supported by said frame intermediate its ends, a fluidreceptacle coupled to said arm on one side of said pivot, meanscomprising a counter weight coupled to said arm on the other side ofsaid pivot, and said means for enabling said alarm is disposed adjacentsaid alarm for actuation thereby if the weight of dialysis fluid on saidfluid receptacle is insufficient to overcome the force of said counterweight means, fluidflow conduits interconnected between said first andsecond means, said second means and said catheter, and said catheter andsaid third means, fourth means for regulating the flow of dialysis fluidin said conduits between said first and second means and said catheterin said third means, fifth means-for regulating the flow of dialysisfluid between said second means and said catheter, and from said thirdmeans, and means for controlling said fourth and fifth means toalternately permit flow of dialysis fluid in the conduits regulatedthereby so that the dialysis fluid is permitted to flow through saidapparatus and the patient and then from said third means, said controlmeans comprises a shaft, first and second cams mounted on said shaft,one of said cams controlling said fourth means, and other camcontrolling said fifth means, energizable means for rotating said shaft,and means for selectively energizing and de-energizing said energizablemeans to selectively rotate said shaft.

8. A dialysis apparatus comprising first and second means for regulatingthe flow of dialysis fluid through said apparatus, means coupling saidfirst and second regulating means to each other so that when saidcoupling means is a first position said first regulating means stops theflow of dialysis fluid and said second regulating means permits the flowof dialysis fluid, and when said coupling means is in a second positionsaid first regulating means permits the flow of dialysis fluid whilesaid second regulating means stops the flow of dialysis fluid,selectively energizable means for alternatively positioning saidcoupling means between its first and second positions, said selectivelyenergizable means being mechanically connected to said coupling means,first, second and third timers, said first timer for controlling theduration of time in which said coupling means is in a first position,said first timer including means to emit a control signal when saidfirst timer times out, electrical means for transmitting said controlsignal from said first timer to said selectively energizable means, saidselectively energizable means adapted to be energized in response tosaid control signal so that said selectively energizable means causessaid coupling means to be positioned in the second position, saidelectrical means also to transmit said control signal to said second andthird timers, said second and third timers to automatically reset andstart timing out in response to such signal, said third timer forcontrolling the duration of time in which said coupled regulating meansare in the second position, said third timer including means to emit acontrol signal when said third timer times out, electrical means fortransmitting said control signal from said third timer to saidselectively energizable means, said selectively energizable meansadapted to be energized in response to said control signal so that saidselectively energizable means causes said coupling means to bepositioned in the first position, said electrical means also to transmitsaid control signal to said first timer, said first timer toautomatically reset and start timing out in response to such signal, anenergizable alarm and a switch, said switch being operative to enablesaid alarm upon a condition, said second timer having a shorter timingduration than said third timer and being electrically connected to saidthird timer and said energizable alarm so that if the alarm is enabledwhen said second timer times out, said alarm is energized and said thirdtimer stops timing out until said condition no longer exists.

9. A dialysis apparatus defined in claim 8, including overriding meansfor selectively generating a control signal to said first timer in saidselectively energizable means, said first timer to automatically rewindand start timing out in response to said control signal, saidselectively energizable means to be energized in response to saidcontrol signal so that selectively energizable means causes saidcoupling means to be positioned in the first position, said overridingmeans to be operable independently of said first, second or thirdtimers.

10. A dialysis apparatus defined in claim 8, including overriding meansfor selectively generating a control signal to said second and thirdtimers and to said selectively energizable means, said second and thirdtimers to automatically rewind and start timing out in response to saidcontrol signal, said selectively energizable means to be energized inresponse to said control signalso that selectively energizable meanscauses said coupling means to be positioned in the second position, saidoverriding means to be operable independently of said first, second orthird timers.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, DatedMZa-rCh 25,

Inventor(s) Norman Lasker and Bruce E. Jarrell It is certified thaterror appears in the above-identified patent 0 and that said LettersPatent are hereby corrected as shown below:

In Claim 1, line 11 delete "in" and substitute therefor--and-.

In Claim 1, line 13 delete "and" first occurrence and substitutetherefor in V Signed and Scaled this eighteenth Day of May 1976 sun; 6 ll A (test:

RUTH C. MASON C. MARSHALL DANN Am'sting Ofl'iflr (ummissinm'r of Parentsand Trademarks UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 63 I Dated Mar h 5, 1975 lnventofls) Norman Lasker and BruceE. Jarrell It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

In Claim 1, line 11 delete "in" and substitute therefor--and--.

In Claim 1, line 13 delete "and" first occurrence and substitutetherefor in V Signed and Scaled this eighteenth Day Of May 1976 I [SEAL]Arrest:

RUTH C. MASON C. MARSHALL DANN 195N718 17 (ummissionvr nj'lan'ms andTrademarks

1. A dialysis apparatus comprising first means for supplying dialysisfluid, second means for measuring a predetermined quantity of dialysisfluid, a catheter, third means for detecting a minimum quantity ofdialysis fluid, means for supporting said first means above said secondmeans, said second means above said catheter, and said third means belowsaid catheter so that dialysis fluid moves through said apparatus underthe force of gravity, fluid flow conduits interconnected between saidfirst and second means, said second means and said catheter and saidcatheter in said third means, fourth means for regulating the flow ofdialysis fluid and said conduits between said first and second means andsaid catheter and said third means, fifth means for regulating the flowof dialysis fluid between said second means and said catheter, and fromsaid third means, and means for controlling said fourth and fifth meansto alternately permit flow of dialysis fluid in the conduits regulatedthereby so that the dialysis fluid is permitted to flow through saidapparatus and a patient and then from said third means.
 2. A dialysisapparatus as defined in claim 1 including an alarm, means coupling saidthird means to said alarm, and means for enabling said alarm if saidthird means fails to detect a minimum quantity of dialysis fluid.
 3. Adialysis apparatus as defined in claim 2 wherein said third meanscomprises a frame, an arm, said arm being pivotally supported by saidframe intermediate its ends, a fluid receptacle coupled to said arm onone side of said pivot, means comprising a counterweight coupled to saidarm on the other side of said pivot, and said means for enabling saidalarm is disposed adjacent said arm for actuation thereby if the weightof dialysis fluid in said fluid receptacle is insufficient to overcomethe force of said counterweight means.
 4. A dialysis apparatus asdefined in claim 1 wherein said second means includes means for heatingdialysis liquid therein to a predetermined temperature.
 5. A dialysisapparatus as defined in claim 1 including a fluid flow conduit extendingfrom said third means, and a discharge receptacle connected to said lastnamed fluid flow conduit to receive dialysis fluid from said thirdmeans.
 6. A dialysis apparatus as defined in claim 1 wherein saidcontrol means comprises a shaft, first and second cams mounted on saidshaft, one of said cams controlling said fourth means, the other camcontrolling said fifth means, energizable means for rotating said shaft,and means for selectively energizing and de-energizing said energizablemeans to selectively rotate said shaft.
 7. A dialysis apparatuscomprising first means for supplying dialysis fluid, second means formeasuring a predetermined quantity of dialysis fluid, a catheter, thirdmeans for detecting a minimum quantity of diAlysis fluid, said thirdmeans comprises a frame, an arm, said arm being pivotedly supported bysaid frame intermediate its ends, a fluid receptacle coupled to said armon one side of said pivot, means comprising a counter weight coupled tosaid arm on the other side of said pivot, and said means for enablingsaid alarm is disposed adjacent said alarm for actuation thereby if theweight of dialysis fluid on said fluid receptacle is insufficient toovercome the force of said counter weight means, fluid flow conduitsinterconnected between said first and second means, said second meansand said catheter, and said catheter and said third means, fourth meansfor regulating the flow of dialysis fluid in said conduits between saidfirst and second means and said catheter in said third means, fifthmeans for regulating the flow of dialysis fluid between said secondmeans and said catheter, and from said third means, and means forcontrolling said fourth and fifth means to alternately permit flow ofdialysis fluid in the conduits regulated thereby so that the dialysisfluid is permitted to flow through said apparatus and the patient andthen from said third means, said control means comprises a shaft, firstand second cams mounted on said shaft, one of said cams controlling saidfourth means, and other cam controlling said fifth means, energizablemeans for rotating said shaft, and means for selectively energizing andde-energizing said energizable means to selectively rotate said shaft.8. A dialysis apparatus comprising first and second means for regulatingthe flow of dialysis fluid through said apparatus, means coupling saidfirst and second regulating means to each other so that when saidcoupling means is a first position said first regulating means stops theflow of dialysis fluid and said second regulating means permits the flowof dialysis fluid, and when said coupling means is in a second positionsaid first regulating means permits the flow of dialysis fluid whilesaid second regulating means stops the flow of dialysis fluid,selectively energizable means for alternatively positioning saidcoupling means between its first and second positions, said selectivelyenergizable means being mechanically connected to said coupling means,first, second and third timers, said first timer for controlling theduration of time in which said coupling means is in a first position,said first timer including means to emit a control signal when saidfirst timer times out, electrical means for transmitting said controlsignal from said first timer to said selectively energizable means, saidselectively energizable means adapted to be energized in response tosaid control signal so that said selectively energizable means causessaid coupling means to be positioned in the second position, saidelectrical means also to transmit said control signal to said second andthird timers, said second and third timers to automatically reset andstart timing out in response to such signal, said third timer forcontrolling the duration of time in which said coupled regulating meansare in the second position, said third timer including means to emit acontrol signal when said third timer times out, electrical means fortransmitting said control signal from said third timer to saidselectively energizable means, said selectively energizable meansadapted to be energized in response to said control signal so that saidselectively energizable means causes said coupling means to bepositioned in the first position, said electrical means also to transmitsaid control signal to said first timer, said first timer toautomatically reset and start timing out in response to such signal, anenergizable alarm and a switch, said switch being operative to enablesaid alarm upon a condition, said second timer having a shorter timingduration than said third timer and being electrically connected to saidthird timer and said energizable alarm so that if the alarm is enabledwhen said second timer times out, said alarm is enErgized and said thirdtimer stops timing out until said condition no longer exists.
 9. Adialysis apparatus defined in claim 8, including overriding means forselectively generating a control signal to said first timer in saidselectively energizable means, said first timer to automatically rewindand start timing out in response to said control signal, saidselectively energizable means to be energized in response to saidcontrol signal so that selectively energizable means causes saidcoupling means to be positioned in the first position, said overridingmeans to be operable independently of said first, second or thirdtimers.
 10. A dialysis apparatus defined in claim 8, includingoverriding means for selectively generating a control signal to saidsecond and third timers and to said selectively energizable means, saidsecond and third timers to automatically rewind and start timing out inresponse to said control signal, said selectively energizable means tobe energized in response to said control signal so that selectivelyenergizable means causes said coupling means to be positioned in thesecond position, said overriding means to be operable independently ofsaid first, second or third timers.